Rumble strip noise/dummy lights

Bought on 05 w/ 67K miles about 3 months. Just recently at around 40 MPH, there is a noise and feel that is best described as running over rumble strips on the side of the highway. Only last for couple of seconds. Handles good, no shimmy in the wheel other than that. Very odd. Suggestions?? Did not do this when we got it, recent.

Also, oil light comes on periodically, even though oil is full and there is a very small yellow light under the speedometer that shows "type 43". Clueless as to what this could be.

Any help appreciated.